Jajoo H K, Burcham P C, Goda Y, Blair I A, Marnett L J
A. B. Hancock, Jr., Memorial Laboratory for Cancer Research, Department of Biochemistry, Vanderbilt University School of Medicine, Nashville, Tennessee 37232-0146.
Chem Res Toxicol. 1992 Nov-Dec;5(6):870-5. doi: 10.1021/tx00030a022.
A method is described for detection and quantitation of the major malondialdehyde-guanine adduct (M1G) based on thermospray liquid chromatography/mass spectrometry. A stable isotope analog of M1G ([2H2]M1G) was used as an internal standard. Thermospray mass spectra of M1G and [2H2]M1G showed intense protonated molecular (MH+) ions that were suitable for use in quantitation of M1G. M1G was purified from human urine and reduced with NaBH4 to a dihydro derivative that was cleanly separated from the contaminants in the urine. The detection limit of reduced M1G by thermospray liquid chromatography/mass spectrometry in the selected ion monitoring mode was 250 fmol on column. Six human urine samples were analyzed, and the concentrations of M1G were below the limit of detection of the assay (500 fmol/mL).
描述了一种基于热喷雾液相色谱/质谱法检测和定量主要丙二醛-鸟嘌呤加合物(M1G)的方法。使用M1G的稳定同位素类似物([2H2]M1G)作为内标。M1G和[2H2]M1G的热喷雾质谱显示出强烈的质子化分子(MH+)离子,适用于M1G的定量分析。从人尿液中纯化M1G,并用NaBH4将其还原为二氢衍生物,该衍生物可与尿液中的污染物清晰分离。在选定离子监测模式下,热喷雾液相色谱/质谱法对还原型M1G的检测限为柱上250 fmol。分析了六个人类尿液样本,M1G的浓度低于该检测方法的检测限(500 fmol/mL)。